1. Field of the Invention
The present invention relates to an image display apparatus with a device for forming an image such as an electron-emitting device wired in a matrix, and more particularly, it relates to an image display apparatus such as a television-receiver and a display unit that is provided with a phosphor screen which receives an electron beam ejected from an image-forming apparatus and emits light, or which receives a television signal and a display signal of a computer or the like and displays an image by emitting light of itself.
2. Related Background Art
An image display apparatus provided with a cool-cathode device and configuration in which, to adjust a decrease of brightness resulting from a voltage drop by wiring resistance such as an electrical connection wiring to the cold-cathode device, the adjusted data is calculated by statistical operation and requested and adjusted values of an electron beam are combined is disclosed in Japanese Patent Application Laid-Open No. 8-248920.
The configuration of the image display apparatus described in this publication is shown in FIG. 26.
The configuration according to the data adjustment in this apparatus is roughly as follows.
First, 1-line brightness data of a digital image signal is added by an adder 208 and adjusted factor data that corresponds to this added value is read from a memory 207.
On the other hand, after the digital image signal is converted serially/in parallel in a shift register 204 and held in a latch 205 in a predetermined time, it is input to a multiplier 208 provided for each column wiring in a predetermined timing.
The brightness data and the adjusted data read from the memory 207 are multiplied in the multiplier 208 for each column wiring and the adjusted data obtained is transferred to a modulation signal generator 209. A modulation signal that corresponds to the adjusted data is generated in the modulation signal generator 209 and an image is displayed on a display panel based on this modulation signal.
Hereupon, like the addition processing of the 1-line brightness data of the digital image signal in the adder 208, such statistical operation processing that calculates the sum and the average for the digital image signal is performed and adjustment is performed based on this value.
In the aforementioned conventional configuration, there have been required large-scale hardwares such as a multiplier for each column wiring, a memory for outputting adjusted data, and an adder for assigning an address signal to the memory.
The present invention has been made to solve the problem of such prior art, and the object is to provide an image display-apparatus that can adjust a change of a drive condition of each device due to the electrical resistance that a matrix wiring of a display panel has using less hardware than before.